title: Stimulus detection after interruption of the feedforward response in a backward masking paradigm.
abstract: In backward masking, a target stimulus is rendered invisible by the presentation of a second stimulus, the mask. When the mask is effective, neural responses to the target are suppressed. Nevertheless, weak target responses sometimes may produce a behavioural response. It remains unclear whether the reduced target response is a purely feedforward response or that it includes recurrent activity. Using a feedforward neural network of biological plausible spiking neurons, we tested whether a transient spike burst is sufficient for face categorization. After training the network, the system achieved face/non-face categorization for sets of grayscale images. In a backward masking paradigm, the transient burst response was cut off thereby reducing the feedforward target response. Despite the suppressed feedforward responses stimulus classification remained robust. Thus according to our model data stimulus detection is possible with purely, suppressed feedforward responses.
authors.affiliation: Department of Basic Psychology, Faculty of Psychology, University of Barcelona (UB), Pg. Vall d' Hebron 171, 08035 Barcelona, Spain.
authors.forename: August
authors.initials: A
authors.lastname: Romeo
authors.forename: Maria Sole
authors.initials: MS
authors.lastname: Puig
authors.forename: Laura Pérez
authors.initials: LP
authors.lastname: Zapata
authors.forename: Joan
authors.initials: J
authors.lastname: Lopez-Moliner
authors.forename: Hans
authors.initials: H
authors.lastname: Supèr
keywords: Backward masking; Computational modeling; Face categorization; Face detection